Exception Propagation

Hi........ Ranchians......... Please tell me How the Exception is propagated through out the program? What are the Checked Exception & Unchecked Exception? Please tell me the difference of 2. Is there are 2 different ways of handling these 2? I'm cnfused abt it,please tell me the correct answers.

Exceptions propagate up through block structure of a Java method, and then up the method call stack. If an exception is not caught by the block of code that throws it, it propagates to the next higher enclosing block of code. If it is not caught there, it propagates up again. If it is not caught anywhere in the method, it propagates to the invoking method, where it again propagates through the block structure. If an exception is never caught, it propagates all the way to the main() method from which the program started, and causes the Java interpreter to print an error message and a stack trace and exit.